生态学报
生態學報
생태학보
ACTA ECOLOGICA SINICA
2009年
12期
6785-6792
,共8页
史志华%陈利顶%杨长春%闫峰陵%彭业轩
史誌華%陳利頂%楊長春%閆峰陵%彭業軒
사지화%진리정%양장춘%염봉릉%팽업헌
土质道路%径流%土壤流失%模拟降雨试验%三峡库区
土質道路%徑流%土壤流失%模擬降雨試驗%三峽庫區
토질도로%경류%토양류실%모의강우시험%삼협고구
unpaved road%runoff%soil loss%simulated rainfall tests%the Three Gorges Reservoir Area
以三峡库区王家桥小流域为研究区,通过野外调查选择了5个典型路段,在1.0 mm min~(-1)模拟降雨条件下研究了土质道路降雨-径流-泥沙关系.结果表明,土质道路被高度压实,但使用强度和管护方式差异致使容重、路面浮土、杂草盖度、饱和导水率等差异显著.土质道路仅需1~3 mm降雨就能产生地表径流,7~10 mm的降雨使径流趋于稳定,径流系数超过60%,特别是车流量较大干道的径流系数超过70%,平均和峰值径流量达0.69 mm min~(-1)和0.84 mm min~(-1).土质路面大量浮土致使初始径流含沙量高,然后快速下降并趋于稳定.由于路面浮土量大和在降雨过程中能形成人工细沟的车辙等导致较大车流量干道的土壤流失率是其它路段3~4倍.土质道路的容重和路面浮土与径流系数和土壤流失量呈显著正相关,饱和导水率则呈显著负相关;路面杂草能显著减少径流,防治路面侵蚀.
以三峽庫區王傢橋小流域為研究區,通過野外調查選擇瞭5箇典型路段,在1.0 mm min~(-1)模擬降雨條件下研究瞭土質道路降雨-徑流-泥沙關繫.結果錶明,土質道路被高度壓實,但使用彊度和管護方式差異緻使容重、路麵浮土、雜草蓋度、飽和導水率等差異顯著.土質道路僅需1~3 mm降雨就能產生地錶徑流,7~10 mm的降雨使徑流趨于穩定,徑流繫數超過60%,特彆是車流量較大榦道的徑流繫數超過70%,平均和峰值徑流量達0.69 mm min~(-1)和0.84 mm min~(-1).土質路麵大量浮土緻使初始徑流含沙量高,然後快速下降併趨于穩定.由于路麵浮土量大和在降雨過程中能形成人工細溝的車轍等導緻較大車流量榦道的土壤流失率是其它路段3~4倍.土質道路的容重和路麵浮土與徑流繫數和土壤流失量呈顯著正相關,飽和導水率則呈顯著負相關;路麵雜草能顯著減少徑流,防治路麵侵蝕.
이삼협고구왕가교소류역위연구구,통과야외조사선택료5개전형로단,재1.0 mm min~(-1)모의강우조건하연구료토질도로강우-경류-니사관계.결과표명,토질도로피고도압실,단사용강도화관호방식차이치사용중、로면부토、잡초개도、포화도수솔등차이현저.토질도로부수1~3 mm강우취능산생지표경류,7~10 mm적강우사경류추우은정,경류계수초과60%,특별시차류량교대간도적경류계수초과70%,평균화봉치경류량체0.69 mm min~(-1)화0.84 mm min~(-1).토질로면대량부토치사초시경류함사량고,연후쾌속하강병추우은정.유우로면부토량대화재강우과정중능형성인공세구적차철등도치교대차류량간도적토양류실솔시기타로단3~4배.토질도로적용중화로면부토여경류계수화토양류실량정현저정상관,포화도수솔칙정현저부상관;로면잡초능현저감소경류,방치로면침식.
Unpaved roads are common in mountainous areas. This study examined the characteristics of surface runoff and sediment production from unpaved roads in Wangjiaqiao watershed of the Three Gorges Area of China using a simple portable rainfall simulator. 5 road segments were selected for rainfall simulation. Fifteen rainfall simulation experiments with an intensity of 1.0 mm min~(-1) were carried out on 5 road segments. Cumulative rainfall to runoff was recorded 1-3 mm. The runoff rate generally increased quickly and reached steady level in the first 7-10 min. The runoff coefficient was above 60%, with higher than 70% on the intensively used road segment. The average runoff rate and peak runoff rate were 0.69 mm min~(-1) and 0.84 mm min~(-1), respectively. The greatest erosion was found on the intensively used road, where sediment yield average was 14.38 g L~(-1) and soil loss rate was 12.22 g m~(-2) min~(-1). The sediment concentration increased in the first 1-4 min from the beginning of the rainfall and then decreased steadily due to the loss of fine soil surface particles and porosity changes. The soil loss rate of the intensively used road was 3 and 4 times higher than those from the infrequent traffic road. There is a relationship between sediment yield and the intensity of road usage, due to the creation of artificial rills by vehicles in the rainy periods. Statistical analysis shows that bulk density, saturated hydraulic conductivity, and dust on road surface have significant effects on runoff and soil loss. Stone cover may increase surface runoff, but vegetation cover is very effective in erosion control and runoff reduction.